The PNG Chiefs have spent over $4 million, a third of their cap, yet still need a halfback, hooker and forwards.
They see Cronulla second-rower Briton Nikora starting beside Hudson Young in 2028.
News Corp reports PNG could offer Nikora a tax-free deal, pressing Cronulla to decide his future.
His contract ends in 2027, and he can now negotiate with rival clubs; Cronulla remains undecided amid salary-cap pressure.
William Kennedy, who may seek greater security after annual deals, and Teig Wilton are also off contract then; Wilton is likeliest to stay.
Nikora's form has put him in contention for a Queensland State of Origin debut this year.
He has 180 games, exceeding 20 appearances each season except COVID-hit 2020.
The Queensland and New Zealand representative may cost $600,000 to $700,000, compared with Young's minimum annual cap charge of $1 million.
The Chiefs' cap is also stretched by backline signings Jarome Luai, Brian To'o, Joseph Manu and Zac Lomax.